biotic living factor

The biotic limiting factor is a tree which provides oxygen, and when we cut it down there will be less paper an less oxygen on earth. This tree in my neighborhood is a limiting factor because it provides shelter for birds and if there is no trees they won't have anywhere to live. Trees also provides food for squirrels and other animals we see on earth. All in all if there is no trees then we won't have animals, oxygen, and food.